Modern pay television networks typically employ conditional access modules which provide conditional access to pay television programs distributed via the pay television networks.
The conditional access modules typically enable subscription services, pay-per-view services and impulse-pay-per-view services in which subscribers may view the pay television programs if they agree to pay for the pay television programs.
Aspects of related technology are described in the following references:
U.S. Pat. Nos. 5,282,249 and 5,481,609 to Cohen et al which describe a system for controlling access to broadcast transmissions including a transmitter having a transmission encoder for scrambling the broadcast, a multiplicity of subscriber receivers, each having an identical receiving decoder, containing no cryptographic keys, for descrambling the broadcast and a plurality of selectable and portable executing apparatus each being operatively associatable with a receiving decoder at a partially different given time and each executing generally identical operations to generate a seed for use by the associated receiving decoder to enable the receiving decoder to descramble the broadcast;
U.S. Pat. No. 5,666,412 to Handelman et al which describes a CATV system including a CATV network and apparatus for transmitting over the CATV network information to a multiplicity of subscriber units, each including a CATV decoder and an IC card reader and writer coupled to the CATV decoder, the IC card reader and writer including two separate card receptacles, such that IC cards inserted into the two separate IC card receptacles are separately accessed by the IC card reader and writer;
U.S. Pat. No. 5,774,546 to Handelman et al which describes one IC card with two separate integrated circuits embodied within, wherein each of the separate integrated circuits is separately accessible by an IC card reader and writer;
U.S. patent application Ser. No. 09/105,965 to Tsuria which describes a method for remotely providing parental control in a pay television system in which program guide information is transmitted via a pay television network to a subscriber unit, the program guide information being received and stored at a pay television converter in the subscriber unit, and being displayed on a television upon user request;
PCT patent application PCT/IL98/00307 to Maissel et al which describes a subscriber unit for use in a television system including a television network and transmitting apparatus for transmitting program schedule information, the subscriber unit including a receiving unit for receiving the program schedule information, a profile storage unit for storing at least one viewer preference profile of at least one television viewer, an intelligent agent for customizing the program schedule information based, at least in part, on the viewer preference profile, to produce a program guide including customized program schedule information, and display apparatus for displaying the program guide;
Unpublished Israel patent application 120,684 to Tsuria et al which describes an entertainment system for providing entertainment to a user thereof;
Unpublished Israel patent application 125,141 to Wachtfogel et al which describes a digital television recording message in which sets of parameters provided by a broadcaster, an agent program, and a viewer may be used to enable access to predetermined portions of a television program;
U.S. Pat. No. 5,033,085 to Rew which describes a method for controlling video and audio of a television set using a code in such a manner that a code is set up in a microcomputer of the television set, which is operated normally only when the code is released by input of a key signal corresponding to the code, to output the video and audio signals;
U.S. Pat. No. 5,020,129 to Martin et al which describes remote control of subscriber access to premium programs on a cable television system or the like;
U.S. Pat. Nos. 4,163,254, 4,225,884 and 4,428,589 to Block et al which describe a subscription television system and method in which billing information regarding programs actually viewed by a subscriber of the system is accumulated over non-dedicated telephone lines;
U.S. Pat. No. 5,036,537 to Jeffers et al which describes a geographic black-out method for direct broadcast satellite system;
U.S. Pat. No. 4,989,245 to Bennett which describes a control system and a corresponding method for controlling descrambling within a plurality of jurisdictions of scrambled programs broadcast from at least one of the jurisdictions;
U.S. Pat. No. 5,465,113 to Gilboy which describes a programmable cable controller adapted to accept a time limit and a time period which are input by a viewer and, upon reaching a preset time limit, to block display of a cable channel; and
A publication dated March 1989 of the Eurocrypt access control system for the MAC/Packet family.
The disclosures of all references mentioned above and throughout the present specification are hereby incorporated herein by reference.